A witness said. “People were just going to the church when the bomber entered; otherwise the casualty figure would have been higher,” said Red Cross official Hassan Alhaji Muhammad, who visited the scene of the blast on the outskirts of Potiskum.
A hospital in Potiskum said it had received the bodies.
Suspected Islamist militant gunmen and bombers killed more than 200 people last week in a spate of bloodletting that prompted renewed outrage and calls for an international meeting to coordinate the offensive against Boko Haram.
French President Francois Hollande said the Boko Haram threat was getting stronger and that he was ready to hold a summit, following one in Paris in May 2014, to gather the leaders of countries fighting the insurgents.
There was no immediate claim of responsibility but Potiskum, the commercial capital of Yobe state, has been hit repeatedly by Boko Haram Islamists in their six-year insurgency, including by suicide bombers.
The insurgents have also launched a series of attacks on mosques, villages and markets in neighbouring Borno state in the past few days, claiming more than 200 lives.
Boko Haram are keen to prove they are not a spent force despite a four-nation military offensive that has run them out of captured towns and villages since February this year.
The use of improvised explosive devices and suicide bombings has increased since May 29 when President Muhammadu Buhari took office vowing to crush the rebellion.
